This invention relates to a durable catalyst support; in particular, it relates to a support for catalytic processes involving very high temperatures, e.g., automotive catalysts.
Catalyst supports are usually metal oxides which are generally not very durable at high temperatures, especially in the presence of water/steam. These supports tend to form large crystallites resulting in a lower surface area and possibly enveloping catalytic metals and aiding the metals in sintering. Phase transitions of meta-stable phases such as gamma alumina can occur under forcing conditions (e.g., high temperature, steam), resulting in inferior catalyst support performance. Thermal and/or hydrothermal stability are believed to be important characteristics for a catalyst support in order to attain highly durable performance in automotive emissions control or other catalytic processes that involve temperatures in excess of 800.degree. C.
It is an object of the present invention to provide a catalyst support having good thermal and hydrothermal stability.